RV-3029 Datasheet, PDF (33/67 Pages) MICORO CRYSTAL SWITZERLAND – DTCXO Temperature Compensated Real Time Clock

Micro Crystal
DTCXO Temperature Compensated Real Time Clock / Calendar Module
RV-3029
4.5.1.ALARM INTERRUPT
The generation of Interrupts from the Alarm function is enabled by “AIE” = “1” (bit 0 in register Control_INT).
When all enabled Alarm comparisons first match (wired “AND”) and the Alarm Interrupt is enabled by, the Alarm
Flag “AF” (bit 0 in Register Control_INT Flag) is set to logic = “1”. The Interrupt signal ( INT ) follows the condition of
“AF”.
The Interrupt signal INT follows the condition of Alarm Flag “AF” (bit 0 in register Control_INT Flag), The Alarm
Flag “AF” and the Interrupt signal ( INT ) remain set until cleared by software writing “AF” = “0”.
Once bit “AF” has been cleared, it will only be set again when the time increments and matches the alarm condition
once more.
Alarm Interrupt Control (addresses 01h / 02h…bits description)
Address
Function
Bit 7
Bit 6
Bit 5
01h
Control_INT
X
X
X
Bit 4
SRIE
Bit 3
V2IE
Bit 2
V1IE
Bit 1
TIE
Bit 0
AIE
0
AIE
0
AF is disabled, no Alarm Interrupt generated
1
AF is enabled, AF is set “1”and Alarm Interrupt generated when all
enabled Alarm comparisons first match
02h
Control_INT Flag
X
X
X
SRF
V2IF V1IF
TF
AF
0
AF
0
No Alarm Interrupt generated
Alarm Flag is set “1” when all enabled Alarm comparisons first match,
1
needs to be cleared to clear INT
Bit positions labelled as “X” are not implemented and will return a “0” when read.
Example for Alarm Flag and Alarm INT
Example where “Minute Alarm” is enabled and set to 45 and no other Alarm is enabled.
If bit AIE is enabled, the INT pin follows the condition of bit 0 “AF” in register Control_INT Flag at address 02h.
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